1. Field of the Invention
The present invention relates to a speaker and more particularly, to a basket for speaker that dissipates heat and eliminates noises during vibration of the damper.
2. Description of the Related Art
A speaker is an electro-acoustic transducer that converts electrical signals into sounds loud enough to be heard at a distance. It is used in broadcasting systems, stereo systems, TVs, computers, and various other audio/video electronic products. A speaker uses a voice coil in a magnet system to produce a magnetic induction that causes the voice coil to reciprocate along the axis of the magnet system and to further produce sound waves of different frequencies.
FIG. 5 shows a speaker according to the prior art. According to this design, the speaker comprises a basket A having a sound barrier A1, a cone B suspending in the sound barrier A1, a voice coil former B1 extending downward from the center of the cone B inside the basket A, a voice coil B2 mounted around the voice coil former B1, a flexible surround C joining the periphery of the cone B to the sound barrier A1 of the basket A, the flexible surround C having an arched face C1, a packing ring D fastened to the basket A to hold down the surround C, a sound chamber A11 defined between the cone B and the sound barrier A1, a damper E mounted in the bottom side inside the sound chamber A11 and closely attached to the periphery of the voice coil former B1, a diaphragm F fastened to the center of the cone B at the top, and a tweeter B11 installed in the diaphragm F. This structure of speaker is still not satisfactory in function due to the following drawbacks:
The inside temperature of the sound chamber A11 will rise during vibration of the sound coil B2 in the basket A. However, because the sound chamber A11 is an enclosed chamber, heat cannot be quickly dissipated out of the sound chamber A11 into the outside air.
Because the sound chamber A11 is an enclosed chamber, vibration of the damper E with the voice coil B2 will produce resonance noises that cannot be quickly eliminated by the cone B and will affect the quality of the sound waves.
FIG. 6 shows another structure of speaker according to the prior art. According to this design, the basket G has a plurality of air vents G11 in the periphery of the base G1 thereof for dissipation of heat during vibration of the damper with the voice coil (not shown). However, due to the limitation of the location of the annular rib G2 around the base G1 of the basket G, the size of the air vents G11 is limited. Because the air vents G11 are small and spaced from the damper at a distance, heat cannot be efficiently carried away from the inside space of the basket G. Further, the air vents G11 do not allow circulation of air between the inside space of the basket G and the outside open air, and vibration noises will be accumulated inside the basket G to affect the quality of the sound waves.